JP3216369B2 - Tube composite cable and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable in which a large-diameter main wire and a tube, such as a power transmission conductor and a copper communication cable, are combined, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventional techniques include, for example, Sumitomo Electric,
136, March 1990, p. 139-146
"Application of ABF method to 66kV power optical fiber composite cable"
Describes an example of a tube composite power cable.
FIG. 3 is a cross-sectional view of a conventional tube composite power cable. In the figure, 1 is a main wire and 2 is a tube. In the tube composite power cable shown in FIG.
A 7 mm main wire 1 (coated 325 mm ² conductor) is twisted, and one tube 2 each having an outer diameter of 16 mm and an inner diameter of 6 mm is arranged between the valleys. This tube composite power cable has a capacity of 77 kV,
The tube 2 is twisted at the same pitch as the main wire 1 to have a spiral shape. For example, an optical fiber can be arranged in the tube 2. For the transmission of the optical fiber to the tube 2, the above-mentioned document describes a method using an air flow.

However, in recent years, with the increase in power demand,
Power cables with large conductors are being developed and manufactured. For example, in the case of a power cable having a capacity of 154 kV, if individual tubes are arranged in the valley, the outer diameter of the tube is smaller than that of the main wire. There has been a problem that the twist is loosened, the tube enters the open valley of the main wire and is crushed, and the function of the conduit is lost. With the increase in the size of the conductor, it has been considered to arrange a plurality of tubes independent of each other in order to effectively use the gap between the valleys. However, the problem that the tubes are crushed similarly occurs.

On the other hand, when a plurality of tubes are twisted and assembled to form a tube wire having an outer diameter of about twice that of the tube alone, the problem of severe drop as described above has been eliminated. For example, when an optical fiber is passed through the inside, there has been a problem that the transmission distance is shortened or stopped halfway. In other words, by assembling a plurality of tubes in advance to form a tube wire, the problem of dropping between the main wires opened during installation in a bent portion of a pipeline or the like can be solved, but the gathering pitch of the tube wires is different from that of the main wire. It is considered that the trajectory of the tube has a double spiral shape because the pitch is different from the twisting pitch of the tube wire, and large and small bending occurs at a short pitch, which makes it difficult to transmit the optical fiber.

[0005] In the tube wire, the tube housed in the portion in contact with the main wire changes one after another, and the way of applying the side pressure from the main wire changes. As a result, it is considered that the distortion of the inner diameter of the tube changes in the longitudinal direction, which increases the resistance at the time of transmission and that the transmission of the optical fiber is stopped particularly at a bent portion of the conduit. Can be

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and is intended to prevent the tube from dropping between the main wires and to easily insert the wire into the tube. It is an object of the present invention to provide a tube composite cable having a shape that can be formed and a method for manufacturing the same.

[0007]

According to a first aspect of the present invention, there is provided a method for manufacturing a tube composite cable in which a main wire is twisted with a tube wire obtained by assembling a plurality of tubes. The plurality of tubes are twisted and formed in a direction opposite to the twisting direction of the main wire, and the main wire and the tube wire are twisted in the twisting direction of the main wire.

Further, in the invention according to claim 2,
In a method of manufacturing a tube composite cable in which a tube wire and a main wire in which a plurality of tubes are assembled are twisted,
The present invention is characterized in that a tube wire made by assembling a plurality of tubes straight out is twisted and twisted with a main wire while being twisted, and the tube wire is assembled and integrated so as not to be twisted.

[0009] In the invention according to claim 1 or 2,
The invention according to claim 3 is characterized in that the main wire is a power cable larger than the tube wire, and the tube wire is disposed in one or a plurality of outward valleys formed by the main wire. I have.

According to a fourth aspect of the present invention, in the tube composite cable formed by twisting a main wire and a tube wire in which a plurality of tubes are assembled, the tube wire is formed by integrating the plurality of tubes. The each tube is maintained at a relative position with respect to the center of the tube composite cable in an arbitrary cross-section, and each tube has the same pitch as the twisting pitch of the main wire and the tube wire. The present invention is characterized in that a point at a distance determined for each tube from the center of the tube composite cable is arranged so as to take a single spiral orbit. A power cable larger than the tube wire can be used as the main wire. Further, the tube wire having a structure in which the plurality of tubes are assembled and integrated has an outer shape having an angle corresponding to a valley of the main wire in a part thereof, and the outer shape portion is formed in a valley of the main wire. It can be configured to be arranged.

[0011]

According to the first aspect of the invention, the plurality of tubes are first twisted at the same pitch as the twisting of the main wires and in the direction opposite to the twisting direction of the main wires. Thus, when the tube wire is wound or stored during manufacture, the length of each assembled tube becomes constant, and the specific tube does not expand. next,
When this tube wire is twisted together with the main wire, the plurality of tubes assembled in the tube wire are untwisted, and each tube has a structure of drawing a single spiral orbit around the center of the tube composite cable.

According to the second aspect of the invention, first, a plurality of tubes are straightly assembled to form a tube wire, which is twisted with the main wire while being twisted. As a result, each tube has a structure that draws a single spiral trajectory around the center of the tube composite cable.

According to the third aspect of the present invention, the first aspect is provided.
Alternatively, in the manufacturing method according to the invention described in 2, the power cable larger than the tube wire can be used as the main wire, and one or more tube wires between the outward valleys formed by the power cable are arranged. Accordingly, a tube composite cable that effectively utilizes the gap between the power cables can be manufactured.

According to the fourth aspect of the present invention, a plurality of tubes are integrated and integrated, so that even if a large main wire is used, it does not fall between the main wires. Also,
Each tube maintains a relative position with respect to the center of the tube composite cable in an arbitrary cross section, and the side pressure received by the tube from the main wire or the like is constant. In addition, each tube is arranged so as to take a single spiral at a point at a distance determined for each tube from the center of the tube composite cable at the same pitch as the twisting pitch of the main wire and the tube wire. Therefore, each tube does not have a complicated bend at a short pitch. Therefore, it is possible to easily transmit a wire such as an optical fiber into the tube. As the main wire, an electric power cable larger than the tube wire can be used.

Further, the tube wire having a structure in which a plurality of tubes are assembled and integrated as in the invention according to claim 6 has an outer shape having an angle corresponding to a valley of the main wire at a part thereof. By comprising so that the portion of the outer shape is arranged between the valleys of the main wire, the contact surface between the main wire and the tube wire can be increased, the movement in the front-rear direction, the lateral direction is suppressed, A tube composite cable having a stable structure can be obtained.

[0016]

FIG. 1 is a sectional view showing an embodiment of a tube composite cable according to the present invention. In the figure, 1 is a main wire, 2 is a tube, and 3 is a tube wire. In the tube composite cable having the cross-sectional structure shown in FIG.
And three tube wires 3 having three tubes 2 respectively.

The three tubes 2 are arranged in an equilateral triangle, and a triangular jacket is applied to maintain this shape to form a tube wire 3. In this manner, the plurality of tubes 2 are integrated and twisted with the main wire 1, so that the tubes 2 do not fall between the main wires 1.

The tube wire 3 is rotated at the same pitch as the twisting pitch of the three main wires 1 while the main wire 1 is rotated.
It is twisted. At this time, the tubes are arranged so that the relative positional relationship with respect to the center of the tube composite cable is maintained, so that the cross section of the tube composite cable always has a constant shape based on the center of the tube composite cable. Looking at each tube 2, it is arranged so as to draw a single spiral trajectory equidistant from the center of the tube composite cable. Therefore, the tube 2 does not bend extremely small, and the surface of the tube 2 that is in contact with the main wire 1 is fixed, so that the tube is not subjected to discontinuous lateral pressure deformation.

Furthermore, the triangular shape of the tube wire 3 can be formed so as to match the shape of the valley of the main wire. With such a shape, the tube wire 3 can be densely integrated with the main wire 1. At this time, since the contact surface between the tube wire 3 and the main wire 1 is large, not only the drop of the tube wire 3 into the inside of the main wire 1 is prevented, but also the movement in the front-rear direction and the lateral direction is suppressed, so that the stable. The structure is obtained.

Such a tube composite cable can be manufactured as follows. First, the plurality of tubes 2 are placed in a direction opposite to the direction in which the main wires 1 are twisted,
Twisted at the same pitch as that of main battle material 1,
The tube wire 3 is formed by coating and integrating. Since the tube wire 3 is twisted, the length of the tube 2 becomes constant even when it is wound, for example, and a specific tube does not expand.

Next, the main wire 1 and the tube wire 3 are twisted. At this time, the tube wire 3 is twisted so as to be arranged in a valley between the main wires 1. This twist is applied to the main wire 1
Is performed in the twisting direction, so that the tubes assembled in the tube wire 3 are untwisted. Therefore, the tube wire 3 itself is not twisted, and each tube is connected to the main wire 1.
Is twisted in a single spiral. Thus, a tube composite cable having a cross section as shown in FIG. 1 can be obtained.

Alternatively, by using a tube wire 3 in which a plurality of tubes 2 are gathered straight without being twisted, they are fed while being twisted and twisted with the main wire 1,
A tube composite cable as shown in FIG. 1 in which the tube wire 3 is not twisted and the tube wire 3 is arranged in a single spiral around the main wire 1 can be manufactured.

Next, a specific example of the tube composite cable of the present invention will be described. 4.5m inside diameter as a tube
m, a polyethylene tube having an outer diameter of 6 mm was used.
Three tubes were twisted left at a pitch of 900 mm, and a sheath having a thickness of 15 mm was formed to form a triangular tube wire. A polyethylene-coated copper cable having an outer diameter of 110 mm was used as the main wire. The three main wires and the three tube wires were right-twisted at a pitch of 900 mm to form a tube composite cable. This sectional structure is shown in FIG.

Using such a tube composite cable, an experiment of transmitting an optical fiber through a tube was performed. In the experiment, the outer diameter was 2 m covered with polyethylene foam.
An optical fiber unit having a length of 300 m, a weight of 2 g / m and a length of 300 m was fed by compressed air having a pressure of 7 kg / cm ² . As a result of this experiment, for all the tubes in the tube composite cable, it is possible to transmit an optical fiber having a length of 300 m, and even after laying in a pipeline, the transmission of the optical fiber has no problem, and there were.

Using the same tube as in the above-mentioned specific example, three tubes were assembled in a straight line to form a tube wire. Using three of these tube wires, the three main wires were twisted at a pitch of 900 mm while being twisted to produce a tube composite cable. The cross-sectional structure of this tube composite cable was as shown in FIG.
After the manufacture, the tube composite cable was laid, and a transmission test of the optical fiber was performed. The laying performance of the optical fiber was good.

As a comparative example, three main wires were set at a pitch of 90 m.
m, right-twisted, and three tubes each arranged in three gaps in total of nine tubes were twisted at the same time. During winding, the two tubes were pinched by the main wire and crushed. Also,
When the pipes were laid in a pipe having a radius of 3 m and four 30 ° bends, three more tubes could not transmit optical fibers in addition to the two tubes. This is probably because the tube was crushed during the installation.

Further, as another comparative example, a tube was coated by being twisted rightward at a pitch of 400 mm to produce a tube wire. This tube wire and main wire 3 twisted right
The book was twisted right at a pitch of 900 mm to produce a tube composite cable. Although crushing of the tube did not occur during manufacture, as a result of evaluating the laying performance of the optical fiber,
As for the cable immediately after production, the transmittable distance of the optical fiber was about 60 m. This was much shorter than the tube composite cable using the present invention, and the effect of using a single spiral trajectory when twisting the tubes was confirmed.

FIG. 2 is a sectional view showing a modification of the embodiment of the tube composite cable according to the present invention. In the figure, the same parts as those in FIG.
4 is a sheath. In the above-described example, the form in which the main wire and the tube wire are laid only in the twisted state of the main wire and the tube wire is shown. However, as shown in FIG. And may be integrated. With the tube composite cable having such a configuration, the same operation and effect can be obtained, and the sheath 4
Thereby, the inner tube 2 and the main wire 1 are protected against an external impact.

In the above-described embodiment and specific examples, the case where the number of main wires is three is shown.
Even in the case of four or more, a tube composite cable can be similarly arranged by arranging a tube wire between valleys of a main wire. Moreover, it is not necessary to arrange tube wires between all the valleys of the main wire, and the number of tube wires can be changed according to the application. Further, the number of tubes constituting the tube wire can also be changed, and it is sufficient if the tube can be configured to have a thickness that does not fall between the main wires. The number of tubes included in each tube wire does not need to be the same, and can be changed as appropriate.

[0030]

As is apparent from the above description, according to the present invention, since the tube takes a single spiral trajectory around the center of the tube composite cable, the optical fiber or the like after the tube composite cable is laid. Can be easily laid. In particular, even when used as a large-capacity power cable in which a large main wire is formed, or as a tube composite cable combined with a super-multi-core copper communication cable, the tube is not crushed. There is an effect that the optical fiber can be stored.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a tube composite cable of the present invention.

FIG. 2 is a cross-sectional view showing a modification of the embodiment of the tube composite cable of the present invention.

FIG. 3 is a cross-sectional view of a conventional tube composite power cable.

[Explanation of symbols]

 1 Main wire 2 Tube 3 Tube wire 4 Sheath.

────────────────────────────────────────────────── (5) References JP-A-5-166422 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01B 7/00 310 G02B 6/44 391 H01B 11/22 H01B 13/00 541 H01B 13/00 555 H01B 13/02

Claims (6)

(57) [Claims] 1. A method of manufacturing a tube composite cable in which a main wire is twisted with a tube wire in which a plurality of tubes are assembled, wherein the tube wire twists the plurality of tubes in a direction opposite to a direction in which the main wire is twisted. A method of manufacturing a tube composite cable, comprising: forming the main wire and the tube wire in a twisting direction of the main wire. 2. A method of manufacturing a tube composite cable in which a tube wire in which a plurality of tubes are gathered and a main wire are twisted, wherein the main wire is drawn out while twisting a tube wire in which the plurality of tubes are gathered straight. A method for manufacturing a tube composite cable, wherein the tube wire is assembled and integrated so as not to be twisted. 3. The power cable according to claim 1, wherein the main wire is a power cable larger than the tube wire, and the tube wire is arranged in one or more of the outward valleys formed by the main wire. Or the method for manufacturing a tube composite cable according to 2. 4. In a tube composite cable formed by twisting a main wire and a tube wire obtained by assembling a plurality of tubes, the tube wire is formed by integrating the plurality of tubes, and each of the tubes is optional. The cross-section of the tube composite cable maintains a relative position with respect to the center of the tube composite cable, and each of the tubes is spaced from the center of the tube composite cable at the same pitch as the twisting pitch of the main wire and the tube wire. A tube composite cable, which is arranged so as to take a single spiral trajectory at a point at a predetermined distance for each tube. 5. The power cable according to claim 4, wherein a power cable larger than the tube wire is used as the main wire.
A tube composite cable according to item 1. 6. The tube wire having a structure in which the plurality of tubes are assembled and integrated has an outer shape having an angle matching a valley of the main wire in a part thereof, and the outer wire portion is formed of a main wire. The tube composite cable according to claim 4, wherein the cable is disposed in a valley of the tube.